Anaerobic Treatment of Coal Gasification Wastewater

1987 ◽  
Vol 19 (1-2) ◽  
pp. 229-236 ◽  
Author(s):  
Makram T. Suidan ◽  
Peter Fox ◽  
John T. Pfeffer
Keyword(s):  
Activated Carbon ◽  
Coal Gasification ◽  
Physical Adsorption ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Anaerobic Treatment ◽  
Partial Replacement ◽  
Anaerobic Culture ◽  
Second Stage ◽  
Coal Gasification Wastewater

A sequence of unit processes consisting of a berl-saddle-packed anaerobic filter, an expanded-bed, granular activated carbon anaerobic reactor and an activated sludge nitrification system was employed for the treatment of synthetically prepared coal gasification wastewater. After acclimation, the coal gasification wastewater was fed to the treatment process train at three different chemical oxygen demand levels; these were 1,513. 3,027, and 7,567 mg/ℓ, respectively. No biological activity was observed in the first-stage filter, while excellent removal of organic matter was achieved in the second and third stages of the treatment systems. However, toxicity to the anaerobic culture in the second-stage reactor was observed during the second and third loading levels. This toxicity was overcome by employing a partial replacement schedule of the granular activated carbon medium in the reactor. This study represents an example of how biodegradation and physical adsorption may be successfully combined during the treatment of wastewaters containing toxic or inhibitory substances.

Adsorption Kinetics of Lignite Activated Carbon in Treating Coal Gasification Wastewater

2014 ◽  
Vol 1073-1076 ◽  
pp. 955-959
Author(s):  
Ruo Zheng Li ◽  
Hong Yang ◽  
Xin Jin
Keyword(s):  
Activated Carbon ◽  
Coal Gasification ◽  
Adsorption Process ◽  
Physical Adsorption ◽  
Second Order ◽  
Pseudo Second Order ◽  
Coal Gasification Wastewater ◽  
New Treatment ◽  
Kinetics Of ◽  
Adsorption Activation Energy

Lignite activated carbon was provided through lignite which is treated specially. The adsorption capacity and mechanism of COD from Coal gasification wastewater by lignite activated carbon have been studied.The adsorption capacities of lignite activated carbon at different times were obtained by concentration of COD in the remainder solution. Three simplified kinetic models: pseudo-first-order, pseudo-second-order, intraparticle diffusion equations were adopted to examine the mechanism of the adsorption process. The results showed that the adsorption can be expressed by the pseudo-second-order model. The adsorption balance capacity was obtained as 50.8mg·g-1 (298K), and the adsorption balance capacity decreased with increasing of temperature, which showed that the adsorption process was exothermic. The adsorption activation energy (Ea) was calculated as 5.76kJ·mol-1, and it showed that the adsorption process was Physical adsorption. This study explored new treatment channels for lignite comprehensive utilization..

Removal of nitrogen from coal gasification wastewater by nitrosofication and denitrosofication

1998 ◽  
Vol 38 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Junxin Liu ◽  
Weiguang Li ◽  
Xiuheng Wang ◽  
Hongyuan Liu ◽  
Baozhen Wang
Keyword(s):  
Nitrogen Removal ◽  
Coal Gasification ◽  
Oxygen Demand ◽  
Test Results ◽  
New Process ◽  
Scale Test ◽  
Coal Gasification Wastewater ◽  
Total Nitrogen Removal ◽  
Biological Nitrogen ◽  
Bench Scale Test

In this paper, a study of a new process with nitrosofication and denitrosofication for nitrogen removal from coal gasification wastewater is reported. In the process, fibrous carriers were packed in an anoxic tank and an aerobic tank for the attached growth of the denitrifying bacteria and Nitrobacter respectively, and the suspended growth activated sludge was used in an aerobic tank for the growth of Nitrosomonas. A bench scale test has been carried out on the process, and the test results showed that using the process, 25% of the oxygen demand and 40% of the carbon source demand can be saved, and the efficiency of total nitrogen removal can increase over 10% as compared with a traditional process for biological nitrogen removal.

scholarly journals Study on Chromaticity Removal from Mineral Processing Wastewater with Salicylic Hydroxamic Acid by Granular Activated Carbon Catalyzed Ozonation

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 359
Author(s):  
Liping Zhang ◽  
Shengnian Wu ◽  
Nan Zhang ◽  
Ruihan Yao ◽  
Eryong Wu
Keyword(s):  
Activated Carbon ◽  
Reaction Time ◽  
Hydroxamic Acid ◽  
Ph Value ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Mineral Processing ◽  
Ultraviolet Absorption Spectrum ◽  
Experimental Conditions ◽  
Removal Ratio

Salicylic hydroxamic acid is a novel flotation reagent used in mineral processing. However, it impacts the flotation wastewater leaving behind high chromaticity which limits its reuse and affects discharge for mining enterprises. This study researched ozonation catalyzed by the granular activated carbon (GAC) method to treat the chromaticity of the simulated mineral processing wastewater with salicylic hydroxamic acid. The effects of pH value, ozone (O3) concentration, GAC dosage, and reaction time on chromaticity and chemical oxygen demand (CODCr) removal were discussed. The results of individual ozonation experiments showed that the chromaticity removal ratio reached 79% and the effluent chromaticity exceeded the requirement of reuse and discharge when the optimal experimental conditions were pH value 3, ozone concentration 6 mg/L, and reaction time 40 min. The orthogonal experimental results of catalytic ozonation with GAC on chromaticity removal explained that the chromaticity removal ratio could reach 96.36% and the chromaticity of effluent was only 20 when the optimal level of experimental parameters was pH value 2.87, O3 concentration 6 mg/L, GAC dosage 0.06 g/L, reaction time 60 min respectively. The degradation pathway of salicylic hydroxamic acid by ozonation was also considered based on an analysis with ultraviolet absorption spectrum and high-performance liquid chromatography (HPLC).

scholarly journals Two-stage air stripping combined with hydrolysis acidification process for coal gasification wastewater pretreatment

2019 ◽  
Vol 79 (11) ◽  
pp. 2185-2194 ◽  
Author(s):  
Xiurong Chen ◽  
Xiaoli Sun ◽  
Xiaoxiao Wang ◽  
Peng Xu ◽  
Chenchen Yang ◽  
...  
Keyword(s):  
Biological Treatment ◽  
Coal Gasification ◽  
Ammonium Ion ◽  
Air Stripping ◽  
Second Stage ◽  
Whole Process ◽  
Volatile Phenol ◽  
Coal Gasification Wastewater ◽  
Gas Washing ◽  
Hydrolysis Acidification

Abstract Coal gasification wastewater is mainly from gas washing, condensation and purification processes in the gas furnace with high NH3-N (nitrogen in water in the form of free ammonia (NH3) and ammonium ion (NH4+)), TN (total nitrogen) and refractory organics content, which will inhibit the subsequent biological treatment. The ‘air stripping – hydrolysis acidification – air stripping’ process was proposed as the pretreatment for coal gasification wastewater to improve the biodegradability and nitrogen removal, which could reduce the subsequent biological treatment load. The first-stage air stripping process before hydrolysis acidification could achieve a significant removal of NH3-N (97.0%) and volatile phenol (70.0%), reducing the corresponding toxicity on hydrolysis acidification. The group with air stripping had more abundant microbial communities and a more effective organic degradation performance in hydrolysis acidification than that without air stripping. The second-stage air stripping removed NH3-N released from hydrolysis acidification, and significantly reduced the TN concentration in effluent. The whole process achieved a TN removal from 2,000 ± 100 mg/L to 160 ± 80 mg/L, and a total phenols removal from 700 ± 50 mg/L to 80 ±20 mg/L.

scholarly journals Simultaneous nitrification and denitrification (SND) bioaugmentation with Pseudomonas sp. HJ3 inoculated for enhancing phenol and nitrogen removal in coal gasification wastewater

2019 ◽  
Vol 80 (8) ◽  
pp. 1512-1523
Author(s):  
Weiwei Ma ◽  
Yuxing Han ◽  
Wencheng Ma ◽  
Hongjun Han ◽  
Chunyan Xu ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Nitrogen Removal ◽  
Coal Gasification ◽  
Oxygen Demand ◽  
Community Analysis ◽  
Microbial Community Analysis ◽  
Simultaneous Nitrification And Denitrification ◽  
Pseudomonas Sp ◽  
Coal Gasification Wastewater ◽  
Nitrification And Denitrification

Abstract A simultaneous nitrification and denitrification (SND) bioaugmention system with Pseudomonas sp. HJ3 inoculated was established to explore the potential of simultaneous phenol and nitrogen removal in coal gasification wastewater (CGW). When the concentration of influent chemical oxygen demand (COD) and total phenols (TPh) was 1,765.94 ± 27.43 mg/L and 289.55 ± 10.32 mg/L, the average removal efficiency of COD and TPh at the stable operating stage reached 64.07% ± 0.76% and 74.91% ± 0.33%, respectively. Meanwhile, the average removal efficiency of NH4+-N and total nitrogen (TN) reached 67.96% ± 0.17% and 57.95% ± 0.12%, respectively. The maximum SND efficiency reached 83.51%. Furthermore, SND bioaugmentation performed with good nitrification tolerance of phenol shock load and significantly reduced toxic inhibition of organisms. Additionally, the microbial community analysis indicated that Pseudomonas sp. HJ3 was the predominant bacterium in the SND bioaugmentation system. Moreover, the indigenous nitrogen removal bacteria such as Thauera, Acidovorax and Stenotrophomonas were enriched, which further enhanced the nitrogen removal in the SND bioaugmentation system. The results demonstrated the promising application of SND bioaugmentation for enhancing simultaneous phenol and nitrogen removal in CGW treatment.

scholarly journals Viability of a Single-Stage Unsaturated-Saturated Granular Activated Carbon Biofilter for Greywater Treatment

2020 ◽  
Vol 12 (21) ◽  
pp. 8847
Author(s):  
Ahmed Sharaf ◽  
Bing Guo ◽  
David C. Shoults ◽  
Nicholas J. Ashbolt ◽  
Yang Liu
Keyword(s):  
Activated Carbon ◽  
Removal Rate ◽  
Feeding Strategy ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Complete Removal ◽  
Single Stage ◽  
Chemical Oxygen Demand Removal ◽  
Over Time ◽  
Sewage Source

Compared with conventionally collected sewage, source-diverted greywater has a higher potential for on-site treatment and reuse due to its lower contaminant levels and large volume. A new design of granular activated carbon (GAC) biofilters was developed by incorporating unsaturated and saturated zones in a single stage to introduce an efficient, passive, and easy-to-operate technology for greywater on-site treatment at the household scale. The design was customized for its intended application considering various aspects including the reactor’s configuration, packing media, and feeding strategy. With the highest hydraulic and organic loadings of 1.2 m3 m−2 d−1 and 3.5 kg COD m−2 d−1, respectively, and the shortest retention time of 2.4 h, the system maintained an average total chemical oxygen demand removal rate of 94% with almost complete removal of nutrients throughout its 253 days of operation. The system showed a range of reduction efficacy towards five surrogates representing viruses, bacteria, and Cryptosporidium and Giardia (oo)cysts. A well-functioning biofilm was successfully developed, and its mass and activity increased over time with the highest values observed at the top layers. The key microbes within the biofilter were revealed. Feasibility of the proposed technology was investigated, and implications for design and operation were discussed.

An advanced anaerobic expanded granular sludge bed (AnaEG) for the treatment of coal gasification wastewater

RSC Advances ◽  
2014 ◽  
Vol 4 (101) ◽  
pp. 57580-57586 ◽  
Author(s):  
Chunjie Li ◽  
Salma Tabassum ◽  
Zhenjia Zhang
Keyword(s):  
Industrial Wastewater ◽  
Coal Gasification ◽  
State Of The Art ◽  
Granular Sludge ◽  
Anaerobic Treatment ◽  
High Toxicity ◽  
Coal Gasification Wastewater

A state-of-the-art advanced anaerobic expanded granular sludge bed (AnaEG) was developed for the anaerobic treatment of coal gasification wastewater (typical industrial wastewater with poor biodegradability and high toxicity).

Sign in / Sign up

Export Citation Format

Share Document